Who solved the arianism?

Arianism, a theological doctrine that contended that Jesus Christ was not co-eternal with God the Father, was primarily addressed and condemned at the First Council of Nicaea in 325 AD. This council, convened by Emperor Constantine, produced the Nicene Creed, affirming the divinity of Christ and his consubstantiality with the Father. Key figures in opposing Arianism included Athanasius of Alexandria, who became a staunch defender of Nicene orthodoxy. The resolution of the Arian controversy evolved over several centuries, with ongoing debates and reaffirmations of the Nicene Creed in subsequent councils.